/* ***************************************************************************
 *
 * tttypes.h
 *
 * Basic SFNT/TrueType type definitions and interface (specification
 * only).
 *
 * Copyright (C) 1996-2021 by
 * David Turner, Robert Wilhelm, and Werner Lemberg.
 *
 * This file is part of the FreeType project, and may only be used,
 * modified, and distributed under the terms of the FreeType project
 * license, LICENSE.TXT.  By continuing to use, modify, or distribute
 * this file you indicate that you have read the license and
 * understand and accept it fully.
 *
 */


#ifndef TTTYPES_H_
#define TTTYPES_H_


#include <freetype/tttables.h>
#include <freetype/internal/ftobjs.h>
#include <freetype/ftcolor.h>

#ifdef TT_CONFIG_OPTION_GX_VAR_SUPPORT
#include <freetype/ftmm.h>
#endif


FT_BEGIN_HEADER


/* *********************************************************************** */
/* *********************************************************************** */
/* *********************************************************************** */
/* **                                                                   ** */
/* **                                                                   ** */
/* **             REQUIRED TRUETYPE/OPENTYPE TABLES DEFINITIONS         ** */
/* **                                                                   ** */
/* **                                                                   ** */
/* *********************************************************************** */
/* *********************************************************************** */
/* *********************************************************************** */


/* *************************************************************************
 *
 * @struct:
 * TTC_HeaderRec
 *
 * @description:
 * TrueType collection header.  This table contains the offsets of the
 * font headers of each distinct TrueType face in the file.
 *
 * @fields:
 * tag ::
 * Must be 'ttc~' to indicate a TrueType collection.
 *
 * version ::
 * The version number.
 *
 * count ::
 * The number of faces in the collection.  The specification says this
 * should be an unsigned long, but we use a signed long since we need
 * the value -1 for specific purposes.
 *
 * offsets ::
 * The offsets of the font headers, one per face.
 */
typedef struct TTC_HeaderRec_ {
    FT_ULong tag;
    FT_Fixed version;
    FT_Long count;
    FT_ULong *offsets;
} TTC_HeaderRec;


/* *************************************************************************
 *
 * @struct:
 * SFNT_HeaderRec
 *
 * @description:
 * SFNT file format header.
 *
 * @fields:
 * format_tag ::
 * The font format tag.
 *
 * num_tables ::
 * The number of tables in file.
 *
 * search_range ::
 * Must be '16 * (max power of 2 <= num_tables)'.
 *
 * entry_selector ::
 * Must be log2 of 'search_range / 16'.
 *
 * range_shift ::
 * Must be 'num_tables * 16 - search_range'.
 */
typedef struct SFNT_HeaderRec_ {
    FT_ULong format_tag;
    FT_UShort num_tables;
    FT_UShort search_range;
    FT_UShort entry_selector;
    FT_UShort range_shift;

    FT_ULong offset; /* not in file */
} SFNT_HeaderRec, *SFNT_Header;


/* *************************************************************************
 *
 * @struct:
 * TT_TableRec
 *
 * @description:
 * This structure describes a given table of a TrueType font.
 *
 * @fields:
 * Tag ::
 * A four-bytes tag describing the table.
 *
 * CheckSum ::
 * The table checksum.  This value can be ignored.
 *
 * Offset ::
 * The offset of the table from the start of the TrueType font in its
 * resource.
 *
 * Length ::
 * The table length (in bytes).
 */
typedef struct TT_TableRec_ {
    FT_ULong Tag;      /*        table type */
    FT_ULong CheckSum; /*    table checksum */
    FT_ULong Offset;   /* table file offset */
    FT_ULong Length;   /*      table length */
} TT_TableRec, *TT_Table;


/* *************************************************************************
 *
 * @struct:
 * TT_LongMetricsRec
 *
 * @description:
 * A structure modeling the long metrics of the 'hmtx' and 'vmtx'
 * TrueType tables.  The values are expressed in font units.
 *
 * @fields:
 * advance ::
 * The advance width or height for the glyph.
 *
 * bearing ::
 * The left-side or top-side bearing for the glyph.
 */
typedef struct TT_LongMetricsRec_ {
    FT_UShort advance;
    FT_Short bearing;
} TT_LongMetricsRec, *TT_LongMetrics;


/* *************************************************************************
 *
 * @type:
 * TT_ShortMetrics
 *
 * @description:
 * A simple type to model the short metrics of the 'hmtx' and 'vmtx'
 * tables.
 */
typedef FT_Short TT_ShortMetrics;


/* *************************************************************************
 *
 * @struct:
 * TT_NameRec
 *
 * @description:
 * A structure modeling TrueType name records.  Name records are used to
 * store important strings like family name, style name, copyright,
 * etc. in _localized_ versions (i.e., language, encoding, etc).
 *
 * @fields:
 * platformID ::
 * The ID of the name's encoding platform.
 *
 * encodingID ::
 * The platform-specific ID for the name's encoding.
 *
 * languageID ::
 * The platform-specific ID for the name's language.
 *
 * nameID ::
 * The ID specifying what kind of name this is.
 *
 * stringLength ::
 * The length of the string in bytes.
 *
 * stringOffset ::
 * The offset to the string in the 'name' table.
 *
 * string ::
 * A pointer to the string's bytes.  Note that these are usually UTF-16
 * encoded characters.
 */
typedef struct TT_NameRec_ {
    FT_UShort platformID;
    FT_UShort encodingID;
    FT_UShort languageID;
    FT_UShort nameID;
    FT_UShort stringLength;
    FT_ULong stringOffset;

    /* this last field is not defined in the spec */
    /* but used by the FreeType engine            */

    FT_Byte *string;
} TT_NameRec, *TT_Name;


/* *************************************************************************
 *
 * @struct:
 * TT_LangTagRec
 *
 * @description:
 * A structure modeling language tag records in SFNT 'name' tables,
 * introduced in OpenType version 1.6.
 *
 * @fields:
 * stringLength ::
 * The length of the string in bytes.
 *
 * stringOffset ::
 * The offset to the string in the 'name' table.
 *
 * string ::
 * A pointer to the string's bytes.  Note that these are UTF-16BE
 * encoded characters.
 */
typedef struct TT_LangTagRec_ {
    FT_UShort stringLength;
    FT_ULong stringOffset;

    /* this last field is not defined in the spec */
    /* but used by the FreeType engine            */

    FT_Byte *string;
} TT_LangTagRec, *TT_LangTag;


/* *************************************************************************
 *
 * @struct:
 * TT_NameTableRec
 *
 * @description:
 * A structure modeling the TrueType name table.
 *
 * @fields:
 * format ::
 * The format of the name table.
 *
 * numNameRecords ::
 * The number of names in table.
 *
 * storageOffset ::
 * The offset of the name table in the 'name' TrueType table.
 *
 * names ::
 * An array of name records.
 *
 * numLangTagRecords ::
 * The number of language tags in table.
 *
 * langTags ::
 * An array of language tag records.
 *
 * stream ::
 * The file's input stream.
 */
typedef struct TT_NameTableRec_ {
    FT_UShort format;
    FT_UInt numNameRecords;
    FT_UInt storageOffset;
    TT_NameRec *names;
    FT_UInt numLangTagRecords;
    TT_LangTagRec *langTags;
    FT_Stream stream;
} TT_NameTableRec, *TT_NameTable;


/* *********************************************************************** */
/* *********************************************************************** */
/* *********************************************************************** */
/* **                                                                   ** */
/* **                                                                   ** */
/* **             OPTIONAL TRUETYPE/OPENTYPE TABLES DEFINITIONS         ** */
/* **                                                                   ** */
/* **                                                                   ** */
/* *********************************************************************** */
/* *********************************************************************** */
/* *********************************************************************** */


/* *************************************************************************
 *
 * @struct:
 * TT_GaspRangeRec
 *
 * @description:
 * A tiny structure used to model a gasp range according to the TrueType
 * specification.
 *
 * @fields:
 * maxPPEM ::
 * The maximum ppem value to which `gaspFlag` applies.
 *
 * gaspFlag ::
 * A flag describing the grid-fitting and anti-aliasing modes to be
 * used.
 */
typedef struct TT_GaspRangeRec_ {
    FT_UShort maxPPEM;
    FT_UShort gaspFlag;
} TT_GaspRangeRec, *TT_GaspRange;


#define TT_GASP_GRIDFIT 0x01
#define TT_GASP_DOGRAY 0x02


/* *************************************************************************
 *
 * @struct:
 * TT_GaspRec
 *
 * @description:
 * A structure modeling the TrueType 'gasp' table used to specify
 * grid-fitting and anti-aliasing behaviour.
 *
 * @fields:
 * version ::
 * The version number.
 *
 * numRanges ::
 * The number of gasp ranges in table.
 *
 * gaspRanges ::
 * An array of gasp ranges.
 */
typedef struct TT_Gasp_ {
    FT_UShort version;
    FT_UShort numRanges;
    TT_GaspRange gaspRanges;
} TT_GaspRec;


/* *********************************************************************** */
/* *********************************************************************** */
/* *********************************************************************** */
/* **                                                                   ** */
/* **                                                                   ** */
/* **                    EMBEDDED BITMAPS SUPPORT                       ** */
/* **                                                                   ** */
/* **                                                                   ** */
/* *********************************************************************** */
/* *********************************************************************** */
/* *********************************************************************** */


/* *************************************************************************
 *
 * @struct:
 * TT_SBit_MetricsRec
 *
 * @description:
 * A structure used to hold the big metrics of a given glyph bitmap in a
 * TrueType or OpenType font.  These are usually found in the 'EBDT'
 * (Microsoft) or 'bloc' (Apple) table.
 *
 * @fields:
 * height ::
 * The glyph height in pixels.
 *
 * width ::
 * The glyph width in pixels.
 *
 * horiBearingX ::
 * The horizontal left bearing.
 *
 * horiBearingY ::
 * The horizontal top bearing.
 *
 * horiAdvance ::
 * The horizontal advance.
 *
 * vertBearingX ::
 * The vertical left bearing.
 *
 * vertBearingY ::
 * The vertical top bearing.
 *
 * vertAdvance ::
 * The vertical advance.
 */
typedef struct TT_SBit_MetricsRec_ {
    FT_UShort height;
    FT_UShort width;

    FT_Short horiBearingX;
    FT_Short horiBearingY;
    FT_UShort horiAdvance;

    FT_Short vertBearingX;
    FT_Short vertBearingY;
    FT_UShort vertAdvance;
} TT_SBit_MetricsRec, *TT_SBit_Metrics;


/* *************************************************************************
 *
 * @struct:
 * TT_SBit_SmallMetricsRec
 *
 * @description:
 * A structure used to hold the small metrics of a given glyph bitmap in
 * a TrueType or OpenType font.  These are usually found in the 'EBDT'
 * (Microsoft) or the 'bdat' (Apple) table.
 *
 * @fields:
 * height ::
 * The glyph height in pixels.
 *
 * width ::
 * The glyph width in pixels.
 *
 * bearingX ::
 * The left-side bearing.
 *
 * bearingY ::
 * The top-side bearing.
 *
 * advance ::
 * The advance width or height.
 */
typedef struct TT_SBit_Small_Metrics_ {
    FT_Byte height;
    FT_Byte width;

    FT_Char bearingX;
    FT_Char bearingY;
    FT_Byte advance;
} TT_SBit_SmallMetricsRec, *TT_SBit_SmallMetrics;


/* *************************************************************************
 *
 * @struct:
 * TT_SBit_LineMetricsRec
 *
 * @description:
 * A structure used to describe the text line metrics of a given bitmap
 * strike, for either a horizontal or vertical layout.
 *
 * @fields:
 * ascender ::
 * The ascender in pixels.
 *
 * descender ::
 * The descender in pixels.
 *
 * max_width ::
 * The maximum glyph width in pixels.
 *
 * caret_slope_enumerator ::
 * Rise of the caret slope, typically set to 1 for non-italic fonts.
 *
 * caret_slope_denominator ::
 * Rise of the caret slope, typically set to 0 for non-italic fonts.
 *
 * caret_offset ::
 * Offset in pixels to move the caret for proper positioning.
 *
 * min_origin_SB ::
 * Minimum of horiBearingX (resp.  vertBearingY).
 * min_advance_SB ::
 * Minimum of
 *
 * horizontal advance - ( horiBearingX + width )
 *
 * resp.
 *
 * vertical advance - ( vertBearingY + height )
 *
 * max_before_BL ::
 * Maximum of horiBearingY (resp.  vertBearingY).
 *
 * min_after_BL ::
 * Minimum of
 *
 * horiBearingY - height
 *
 * resp.
 *
 * vertBearingX - width
 *
 * pads ::
 * Unused (to make the size of the record a multiple of 32 bits.
 */
typedef struct TT_SBit_LineMetricsRec_ {
    FT_Char ascender;
    FT_Char descender;
    FT_Byte max_width;
    FT_Char caret_slope_numerator;
    FT_Char caret_slope_denominator;
    FT_Char caret_offset;
    FT_Char min_origin_SB;
    FT_Char min_advance_SB;
    FT_Char max_before_BL;
    FT_Char min_after_BL;
    FT_Char pads[2];
} TT_SBit_LineMetricsRec, *TT_SBit_LineMetrics;


/* *************************************************************************
 *
 * @struct:
 * TT_SBit_RangeRec
 *
 * @description:
 * A TrueType/OpenType subIndexTable as defined in the 'EBLC' (Microsoft)
 * or 'bloc' (Apple) tables.
 *
 * @fields:
 * first_glyph ::
 * The first glyph index in the range.
 *
 * last_glyph ::
 * The last glyph index in the range.
 *
 * index_format ::
 * The format of index table.  Valid values are 1 to 5.
 *
 * image_format ::
 * The format of 'EBDT' image data.
 *
 * image_offset ::
 * The offset to image data in 'EBDT'.
 *
 * image_size ::
 * For index formats 2 and 5.  This is the size in bytes of each glyph
 * bitmap.
 *
 * big_metrics ::
 * For index formats 2 and 5.  This is the big metrics for each glyph
 * bitmap.
 *
 * num_glyphs ::
 * For index formats 4 and 5.  This is the number of glyphs in the code
 * array.
 *
 * glyph_offsets ::
 * For index formats 1 and 3.
 *
 * glyph_codes ::
 * For index formats 4 and 5.
 *
 * table_offset ::
 * The offset of the index table in the 'EBLC' table.  Only used during
 * strike loading.
 */
typedef struct TT_SBit_RangeRec_ {
    FT_UShort first_glyph;
    FT_UShort last_glyph;

    FT_UShort index_format;
    FT_UShort image_format;
    FT_ULong image_offset;

    FT_ULong image_size;
    TT_SBit_MetricsRec metrics;
    FT_ULong num_glyphs;

    FT_ULong *glyph_offsets;
    FT_UShort *glyph_codes;

    FT_ULong table_offset;
} TT_SBit_RangeRec, *TT_SBit_Range;


/* *************************************************************************
 *
 * @struct:
 * TT_SBit_StrikeRec
 *
 * @description:
 * A structure used describe a given bitmap strike in the 'EBLC'
 * (Microsoft) or 'bloc' (Apple) tables.
 *
 * @fields:
 * num_index_ranges ::
 * The number of index ranges.
 *
 * index_ranges ::
 * An array of glyph index ranges.
 *
 * color_ref ::
 * Unused.  `color_ref` is put in for future enhancements, but these
 * fields are already in use by other platforms (e.g. Newton).  For
 * details, please see
 *
 * https://developer.apple.com/fonts/TrueType-Reference-Manual/RM06/Chap6bloc.html
 *
 * hori ::
 * The line metrics for horizontal layouts.
 *
 * vert ::
 * The line metrics for vertical layouts.
 *
 * start_glyph ::
 * The lowest glyph index for this strike.
 *
 * end_glyph ::
 * The highest glyph index for this strike.
 *
 * x_ppem ::
 * The number of horizontal pixels per EM.
 *
 * y_ppem ::
 * The number of vertical pixels per EM.
 *
 * bit_depth ::
 * The bit depth.  Valid values are 1, 2, 4, and 8.
 *
 * flags ::
 * Is this a vertical or horizontal strike?  For details, please see
 *
 * https://developer.apple.com/fonts/TrueType-Reference-Manual/RM06/Chap6bloc.html
 */
typedef struct TT_SBit_StrikeRec_ {
    FT_Int num_ranges;
    TT_SBit_Range sbit_ranges;
    FT_ULong ranges_offset;

    FT_ULong color_ref;

    TT_SBit_LineMetricsRec hori;
    TT_SBit_LineMetricsRec vert;

    FT_UShort start_glyph;
    FT_UShort end_glyph;

    FT_Byte x_ppem;
    FT_Byte y_ppem;

    FT_Byte bit_depth;
    FT_Char flags;
} TT_SBit_StrikeRec, *TT_SBit_Strike;


/* *************************************************************************
 *
 * @struct:
 * TT_SBit_ComponentRec
 *
 * @description:
 * A simple structure to describe a compound sbit element.
 *
 * @fields:
 * glyph_code ::
 * The element's glyph index.
 *
 * x_offset ::
 * The element's left bearing.
 *
 * y_offset ::
 * The element's top bearing.
 */
typedef struct TT_SBit_ComponentRec_ {
    FT_UShort glyph_code;
    FT_Char x_offset;
    FT_Char y_offset;
} TT_SBit_ComponentRec, *TT_SBit_Component;


/* *************************************************************************
 *
 * @struct:
 * TT_SBit_ScaleRec
 *
 * @description:
 * A structure used describe a given bitmap scaling table, as defined in
 * the 'EBSC' table.
 *
 * @fields:
 * hori ::
 * The horizontal line metrics.
 *
 * vert ::
 * The vertical line metrics.
 *
 * x_ppem ::
 * The number of horizontal pixels per EM.
 *
 * y_ppem ::
 * The number of vertical pixels per EM.
 *
 * x_ppem_substitute ::
 * Substitution x_ppem value.
 *
 * y_ppem_substitute ::
 * Substitution y_ppem value.
 */
typedef struct TT_SBit_ScaleRec_ {
    TT_SBit_LineMetricsRec hori;
    TT_SBit_LineMetricsRec vert;

    FT_Byte x_ppem;
    FT_Byte y_ppem;

    FT_Byte x_ppem_substitute;
    FT_Byte y_ppem_substitute;
} TT_SBit_ScaleRec, *TT_SBit_Scale;


/* *********************************************************************** */
/* *********************************************************************** */
/* *********************************************************************** */
/* **                                                                   ** */
/* **                                                                   ** */
/* **                  POSTSCRIPT GLYPH NAMES SUPPORT                   ** */
/* **                                                                   ** */
/* **                                                                   ** */
/* *********************************************************************** */
/* *********************************************************************** */
/* *********************************************************************** */


/* *************************************************************************
 *
 * @struct:
 * TT_Post_20Rec
 *
 * @description:
 * Postscript names sub-table, format 2.0.  Stores the PS name of each
 * glyph in the font face.
 *
 * @fields:
 * num_glyphs ::
 * The number of named glyphs in the table.
 *
 * num_names ::
 * The number of PS names stored in the table.
 *
 * glyph_indices ::
 * The indices of the glyphs in the names arrays.
 *
 * glyph_names ::
 * The PS names not in Mac Encoding.
 */
typedef struct TT_Post_20Rec_ {
    FT_UShort num_glyphs;
    FT_UShort num_names;
    FT_UShort *glyph_indices;
    FT_Char **glyph_names;
} TT_Post_20Rec, *TT_Post_20;


/* *************************************************************************
 *
 * @struct:
 * TT_Post_25Rec
 *
 * @description:
 * Postscript names sub-table, format 2.5.  Stores the PS name of each
 * glyph in the font face.
 *
 * @fields:
 * num_glyphs ::
 * The number of glyphs in the table.
 *
 * offsets ::
 * An array of signed offsets in a normal Mac Postscript name encoding.
 */
typedef struct TT_Post_25_ {
    FT_UShort num_glyphs;
    FT_Char *offsets;
} TT_Post_25Rec, *TT_Post_25;


/* *************************************************************************
 *
 * @struct:
 * TT_Post_NamesRec
 *
 * @description:
 * Postscript names table, either format 2.0 or 2.5.
 *
 * @fields:
 * loaded ::
 * A flag to indicate whether the PS names are loaded.
 *
 * format_20 ::
 * The sub-table used for format 2.0.
 *
 * format_25 ::
 * The sub-table used for format 2.5.
 */
typedef struct TT_Post_NamesRec_ {
    FT_Bool loaded;

    union {
        TT_Post_20Rec format_20;
        TT_Post_25Rec format_25;
    } names;
} TT_Post_NamesRec, *TT_Post_Names;


/* *********************************************************************** */
/* *********************************************************************** */
/* *********************************************************************** */
/* **                                                                   ** */
/* **                                                                   ** */
/* **                    GX VARIATION TABLE SUPPORT                     ** */
/* **                                                                   ** */
/* **                                                                   ** */
/* *********************************************************************** */
/* *********************************************************************** */
/* *********************************************************************** */


#ifdef TT_CONFIG_OPTION_GX_VAR_SUPPORT
typedef struct GX_BlendRec_ *GX_Blend;
#endif

/* *********************************************************************** */
/* *********************************************************************** */
/* *********************************************************************** */
/* **                                                                   ** */
/* **                                                                   ** */
/* **              EMBEDDED BDF PROPERTIES TABLE SUPPORT                ** */
/* **                                                                   ** */
/* **                                                                   ** */
/* *********************************************************************** */
/* *********************************************************************** */
/* *********************************************************************** */

/*
 * These types are used to support a `BDF ' table that isn't part of the
 * official TrueType specification.  It is mainly used in SFNT-based bitmap
 * fonts that were generated from a set of BDF fonts.
 *
 * The format of the table is as follows.
 *
 * USHORT version `BDF ' table version number, should be 0x0001.  USHORT
 * strikeCount Number of strikes (bitmap sizes) in this table.  ULONG
 * stringTable Offset (from start of BDF table) to string
 * table.
 *
 * This is followed by an array of `strikeCount' descriptors, having the
 * following format.
 *
 * USHORT ppem Vertical pixels per EM for this strike.  USHORT numItems
 * Number of items for this strike (properties and
 * atoms).  Maximum is 255.
 *
 * This array in turn is followed by `strikeCount' value sets.  Each `value
 * set' is an array of `numItems' items with the following format.
 *
 * ULONG    item_name    Offset in string table to item name.
 * USHORT   item_type    The item type.  Possible values are
 * 0 => string (e.g., COMMENT)
 * 1 => atom   (e.g., FONT or even SIZE)
 * 2 => int32
 * 3 => uint32
 * 0x10 => A flag to indicate a properties.  This
 * is ORed with the above values.
 * ULONG    item_value   For strings  => Offset into string table without
 * the corresponding double quotes.
 * For atoms    => Offset into string table.
 * For integers => Direct value.
 *
 * All strings in the string table consist of bytes and are
 * zero-terminated.
 *
 */

#ifdef TT_CONFIG_OPTION_BDF

typedef struct TT_BDFRec_ {
    FT_Byte *table;
    FT_Byte *table_end;
    FT_Byte *strings;
    FT_ULong strings_size;
    FT_UInt num_strikes;
    FT_Bool loaded;
} TT_BDFRec, *TT_BDF;

#endif /* TT_CONFIG_OPTION_BDF */

/* *********************************************************************** */
/* *********************************************************************** */
/* *********************************************************************** */
/* **                                                                   ** */
/* **                                                                   ** */
/* **                  ORIGINAL TT_FACE CLASS DEFINITION                ** */
/* **                                                                   ** */
/* **                                                                   ** */
/* *********************************************************************** */
/* *********************************************************************** */
/* *********************************************************************** */


/* *************************************************************************
 *
 * This structure/class is defined here because it is common to the
 * following formats: TTF, OpenType-TT, and OpenType-CFF.
 *
 * Note, however, that the classes TT_Size and TT_GlyphSlot are not shared
 * between font drivers, and are thus defined in `ttobjs.h`.
 *
 */


/* *************************************************************************
 *
 * @type:
 * TT_Face
 *
 * @description:
 * A handle to a TrueType face/font object.  A TT_Face encapsulates the
 * resolution and scaling independent parts of a TrueType font resource.
 *
 * @note:
 * The TT_Face structure is also used as a 'parent class' for the
 * OpenType-CFF class (T2_Face).
 */
typedef struct TT_FaceRec_ *TT_Face;


/* a function type used for the truetype bytecode interpreter hooks */
typedef FT_Error (*TT_Interpreter)(void *exec_context);

/* forward declaration */
typedef struct TT_LoaderRec_ *TT_Loader;


/* *************************************************************************
 *
 * @functype:
 * TT_Loader_GotoTableFunc
 *
 * @description:
 * Seeks a stream to the start of a given TrueType table.
 *
 * @input:
 * face ::
 * A handle to the target face object.
 *
 * tag ::
 * A 4-byte tag used to name the table.
 *
 * stream ::
 * The input stream.
 *
 * @output:
 * length ::
 * The length of the table in bytes.  Set to 0 if not needed.
 *
 * @return:
 * FreeType error code.  0 means success.
 *
 * @note:
 * The stream cursor must be at the font file's origin.
 */
typedef FT_Error (*TT_Loader_GotoTableFunc)(TT_Face face, FT_ULong tag, FT_Stream stream, FT_ULong *length);


/* *************************************************************************
 *
 * @functype:
 * TT_Loader_StartGlyphFunc
 *
 * @description:
 * Seeks a stream to the start of a given glyph element, and opens a
 * frame for it.
 *
 * @input:
 * loader ::
 * The current TrueType glyph loader object.
 *
 * glyph index :: The index of the glyph to access.
 *
 * offset ::
 * The offset of the glyph according to the 'locations' table.
 *
 * byte_count ::
 * The size of the frame in bytes.
 *
 * @return:
 * FreeType error code.  0 means success.
 *
 * @note:
 * This function is normally equivalent to FT_STREAM_SEEK(offset)
 * followed by FT_FRAME_ENTER(byte_count) with the loader's stream, but
 * alternative formats (e.g. compressed ones) might use something
 * different.
 */
typedef FT_Error (*TT_Loader_StartGlyphFunc)(TT_Loader loader, FT_UInt glyph_index, FT_ULong offset,
    FT_UInt byte_count);


/* *************************************************************************
 *
 * @functype:
 * TT_Loader_ReadGlyphFunc
 *
 * @description:
 * Reads one glyph element (its header, a simple glyph, or a composite)
 * from the loader's current stream frame.
 *
 * @input:
 * loader ::
 * The current TrueType glyph loader object.
 *
 * @return:
 * FreeType error code.  0 means success.
 */
typedef FT_Error (*TT_Loader_ReadGlyphFunc)(TT_Loader loader);


/* *************************************************************************
 *
 * @functype:
 * TT_Loader_EndGlyphFunc
 *
 * @description:
 * Closes the current loader stream frame for the glyph.
 *
 * @input:
 * loader ::
 * The current TrueType glyph loader object.
 */
typedef void (*TT_Loader_EndGlyphFunc)(TT_Loader loader);


typedef enum TT_SbitTableType_ {
    TT_SBIT_TABLE_TYPE_NONE = 0,
    TT_SBIT_TABLE_TYPE_EBLC, /* `EBLC' (Microsoft), */
                             /* `bloc' (Apple)      */
    TT_SBIT_TABLE_TYPE_CBLC, /* `CBLC' (Google)     */
    TT_SBIT_TABLE_TYPE_SBIX, /* `sbix' (Apple)      */

    /* do not remove */
    TT_SBIT_TABLE_TYPE_MAX

} TT_SbitTableType;


/* OpenType 1.8 brings new tables for variation font support;  */
/* to make the old MM and GX fonts still work we need to check */
/* the presence (and validity) of the functionality provided   */
/* by those tables.  The following flag macros are for the     */
/* field `variation_support'.                                  */
/*                                                             */
/* Note that `fvar' gets checked immediately at font loading,  */
/* while the other features are only loaded if MM support is   */
/* actually requested.                                         */

/* FVAR */
#define TT_FACE_FLAG_VAR_FVAR (1 << 0)

/* HVAR */
#define TT_FACE_FLAG_VAR_HADVANCE (1 << 1)
#define TT_FACE_FLAG_VAR_LSB (1 << 2)
#define TT_FACE_FLAG_VAR_RSB (1 << 3)

/* VVAR */
#define TT_FACE_FLAG_VAR_VADVANCE (1 << 4)
#define TT_FACE_FLAG_VAR_TSB (1 << 5)
#define TT_FACE_FLAG_VAR_BSB (1 << 6)
#define TT_FACE_FLAG_VAR_VORG (1 << 7)

/* MVAR */
#define TT_FACE_FLAG_VAR_MVAR (1 << 8)


/* *************************************************************************
 *
 * TrueType Face Type
 *
 * @struct:
 * TT_Face
 *
 * @description:
 * The TrueType face class.  These objects model the resolution and
 * point-size independent data found in a TrueType font file.
 *
 * @fields:
 * root ::
 * The base FT_Face structure, managed by the base layer.
 *
 * ttc_header ::
 * The TrueType collection header, used when the file is a 'ttc' rather
 * than a 'ttf'.  For ordinary font files, the field `ttc_header.count`
 * is set to 0.
 *
 * format_tag ::
 * The font format tag.
 *
 * num_tables ::
 * The number of TrueType tables in this font file.
 *
 * dir_tables ::
 * The directory of TrueType tables for this font file.
 *
 * header ::
 * The font's font header ('head' table).  Read on font opening.
 *
 * horizontal ::
 * The font's horizontal header ('hhea' table).  This field also
 * contains the associated horizontal metrics table ('hmtx').
 *
 * max_profile ::
 * The font's maximum profile table.  Read on font opening.  Note that
 * some maximum values cannot be taken directly from this table.  We
 * thus define additional fields below to hold the computed maxima.
 *
 * vertical_info ::
 * A boolean which is set when the font file contains vertical metrics.
 * If not, the value of the 'vertical' field is undefined.
 *
 * vertical ::
 * The font's vertical header ('vhea' table).  This field also contains
 * the associated vertical metrics table ('vmtx'), if found.
 * IMPORTANT: The contents of this field is undefined if the
 * `vertical_info` field is unset.
 *
 * num_names ::
 * The number of name records within this TrueType font.
 *
 * name_table ::
 * The table of name records ('name').
 *
 * os2 ::
 * The font's OS/2 table ('OS/2').
 *
 * postscript ::
 * The font's PostScript table ('post' table).  The PostScript glyph
 * names are not loaded by the driver on face opening.  See the
 * 'ttpost' module for more details.
 *
 * cmap_table ::
 * Address of the face's 'cmap' SFNT table in memory (it's an extracted
 * frame).
 *
 * cmap_size ::
 * The size in bytes of the `cmap_table` described above.
 *
 * goto_table ::
 * A function called by each TrueType table loader to position a
 * stream's cursor to the start of a given table according to its tag.
 * It defaults to TT_Goto_Face but can be different for strange formats
 * (e.g.  Type 42).
 *
 * access_glyph_frame ::
 * A function used to access the frame of a given glyph within the
 * face's font file.
 *
 * forget_glyph_frame ::
 * A function used to forget the frame of a given glyph when all data
 * has been loaded.
 *
 * read_glyph_header ::
 * A function used to read a glyph header.  It must be called between
 * an 'access' and 'forget'.
 *
 * read_simple_glyph ::
 * A function used to read a simple glyph.  It must be called after the
 * header was read, and before the 'forget'.
 *
 * read_composite_glyph ::
 * A function used to read a composite glyph.  It must be called after
 * the header was read, and before the 'forget'.
 *
 * sfnt ::
 * A pointer to the SFNT service.
 *
 * psnames ::
 * A pointer to the PostScript names service.
 *
 * mm ::
 * A pointer to the Multiple Masters service.
 *
 * var ::
 * A pointer to the Metrics Variations service.
 *
 * hdmx ::
 * The face's horizontal device metrics ('hdmx' table).  This table is
 * optional in TrueType/OpenType fonts.
 *
 * gasp ::
 * The grid-fitting and scaling properties table ('gasp').  This table
 * is optional in TrueType/OpenType fonts.
 *
 * pclt ::
 * The 'pclt' SFNT table.
 *
 * num_sbit_scales ::
 * The number of sbit scales for this font.
 *
 * sbit_scales ::
 * Array of sbit scales embedded in this font.  This table is optional
 * in a TrueType/OpenType font.
 *
 * postscript_names ::
 * A table used to store the Postscript names of the glyphs for this
 * font.  See the file `ttconfig.h` for comments on the
 * TT_CONFIG_OPTION_POSTSCRIPT_NAMES option.
 *
 * palette_data ::
 * Some fields from the 'CPAL' table that are directly indexed.
 *
 * palette_index ::
 * The current palette index, as set by @FT_Palette_Select.
 *
 * palette ::
 * An array containing the current palette's colors.
 *
 * have_foreground_color ::
 * There was a call to @FT_Palette_Set_Foreground_Color.
 *
 * foreground_color ::
 * The current foreground color corresponding to 'CPAL' color index
 * 0xFFFF.  Only valid if `have_foreground_color` is set.
 *
 * font_program_size ::
 * Size in bytecodes of the face's font program.  0 if none defined.
 * Ignored for Type 2 fonts.
 *
 * font_program ::
 * The face's font program (bytecode stream) executed at load time,
 * also used during glyph rendering.  Comes from the 'fpgm' table.
 * Ignored for Type 2 font fonts.
 *
 * cvt_program_size ::
 * The size in bytecodes of the face's cvt program.  Ignored for Type 2
 * fonts.
 *
 * cvt_program ::
 * The face's cvt program (bytecode stream) executed each time an
 * instance/size is changed/reset.  Comes from the 'prep' table.
 * Ignored for Type 2 fonts.
 *
 * cvt_size ::
 * Size of the control value table (in entries).  Ignored for Type 2
 * fonts.
 *
 * cvt ::
 * The face's original control value table.  Coordinates are expressed
 * in unscaled font units (in 26.6 format).  Comes from the 'cvt~'
 * table.  Ignored for Type 2 fonts.
 *
 * If varied by the `CVAR' table, non-integer values are possible.
 *
 * interpreter ::
 * A pointer to the TrueType bytecode interpreters field is also used
 * to hook the debugger in 'ttdebug'.
 *
 * extra ::
 * Reserved for third-party font drivers.
 *
 * postscript_name ::
 * The PS name of the font.  Used by the postscript name service.
 *
 * glyf_len ::
 * The length of the 'glyf' table.  Needed for malformed 'loca' tables.
 *
 * glyf_offset ::
 * The file offset of the 'glyf' table.
 *
 * is_cff2 ::
 * Set if the font format is CFF2.
 *
 * doblend ::
 * A boolean which is set if the font should be blended (this is for GX
 * var).
 *
 * blend ::
 * Contains the data needed to control GX variation tables (rather like
 * Multiple Master data).
 *
 * variation_support ::
 * Flags that indicate which OpenType functionality related to font
 * variation support is present, valid, and usable.  For example,
 * TT_FACE_FLAG_VAR_FVAR is only set if we have at least one design
 * axis.
 *
 * var_postscript_prefix ::
 * The PostScript name prefix needed for constructing a variation font
 * instance's PS name .
 *
 * var_postscript_prefix_len ::
 * The length of the `var_postscript_prefix` string.
 *
 * horz_metrics_size ::
 * The size of the 'hmtx' table.
 *
 * vert_metrics_size ::
 * The size of the 'vmtx' table.
 *
 * num_locations ::
 * The number of glyph locations in this TrueType file.  This should be
 * one more than the number of glyphs.  Ignored for Type 2 fonts.
 *
 * glyph_locations ::
 * An array of longs.  These are offsets to glyph data within the
 * 'glyf' table.  Ignored for Type 2 font faces.
 *
 * hdmx_table ::
 * A pointer to the 'hdmx' table.
 *
 * hdmx_table_size ::
 * The size of the 'hdmx' table.
 *
 * hdmx_record_count ::
 * The number of hdmx records.
 *
 * hdmx_record_size ::
 * The size of a single hdmx record.
 *
 * hdmx_record_sizes ::
 * An array holding the ppem sizes available in the 'hdmx' table.
 *
 * sbit_table ::
 * A pointer to the font's embedded bitmap location table.
 *
 * sbit_table_size ::
 * The size of `sbit_table`.
 *
 * sbit_table_type ::
 * The sbit table type (CBLC, sbix, etc.).
 *
 * sbit_num_strikes ::
 * The number of sbit strikes exposed by FreeType's API, omitting
 * invalid strikes.
 *
 * sbit_strike_map ::
 * A mapping between the strike indices exposed by the API and the
 * indices used in the font's sbit table.
 *
 * cpal ::
 * A pointer to data related to the 'CPAL' table.  `NULL` if the table
 * is not available.
 *
 * colr ::
 * A pointer to data related to the 'COLR' table.  `NULL` if the table
 * is not available.
 *
 * kern_table ::
 * A pointer to the 'kern' table.
 *
 * kern_table_size ::
 * The size of the 'kern' table.
 *
 * num_kern_tables ::
 * The number of supported kern subtables (up to 32; FreeType
 * recognizes only horizontal ones with format 0).
 *
 * kern_avail_bits ::
 * The availability status of kern subtables; if bit n is set, table n
 * is available.
 *
 * kern_order_bits ::
 * The sortedness status of kern subtables; if bit n is set, table n is
 * sorted.
 *
 * bdf ::
 * Data related to an SFNT font's 'bdf' table; see `tttypes.h`.
 *
 * horz_metrics_offset ::
 * The file offset of the 'hmtx' table.
 *
 * vert_metrics_offset ::
 * The file offset of the 'vmtx' table.
 *
 * sph_found_func_flags ::
 * Flags identifying special bytecode functions (used by the v38
 * implementation of the bytecode interpreter).
 *
 * sph_compatibility_mode ::
 * This flag is set if we are in ClearType backward compatibility mode
 * (used by the v38 implementation of the bytecode interpreter).
 *
 * ebdt_start ::
 * The file offset of the sbit data table (CBDT, bdat, etc.).
 *
 * ebdt_size ::
 * The size of the sbit data table.
 */
typedef struct TT_FaceRec_ {
    FT_FaceRec root;

    TTC_HeaderRec ttc_header;

    FT_ULong format_tag;
    FT_UShort num_tables;
    TT_Table dir_tables;

    TT_Header header;         /* TrueType header table          */
    TT_HoriHeader horizontal; /* TrueType horizontal header     */

    TT_MaxProfile max_profile;

    FT_Bool vertical_info;
    TT_VertHeader vertical; /* TT Vertical header, if present */

    FT_UShort num_names;        /* number of name records  */
    TT_NameTableRec name_table; /* name table              */

    TT_OS2 os2;               /* TrueType OS/2 table            */
    TT_Postscript postscript; /* TrueType Postscript table      */

    FT_Byte *cmap_table; /* extracted `cmap' table */
    FT_ULong cmap_size;

    TT_Loader_GotoTableFunc goto_table;

    TT_Loader_StartGlyphFunc access_glyph_frame;
    TT_Loader_EndGlyphFunc forget_glyph_frame;
    TT_Loader_ReadGlyphFunc read_glyph_header;
    TT_Loader_ReadGlyphFunc read_simple_glyph;
    TT_Loader_ReadGlyphFunc read_composite_glyph;

    /* a typeless pointer to the SFNT_Interface table used to load */
    /* the basic TrueType tables in the face object                */
    void *sfnt;

    /* a typeless pointer to the FT_Service_PsCMapsRec table used to */
    /* handle glyph names <-> unicode & Mac values                   */
    void *psnames;

#ifdef TT_CONFIG_OPTION_GX_VAR_SUPPORT
    /* a typeless pointer to the FT_Service_MultiMasters table used to */
    /* handle variation fonts                                          */
    void *mm;

    /* a typeless pointer to the FT_Service_MetricsVariationsRec table */
    /* used to handle the HVAR, VVAR, and MVAR OpenType tables         */
    void *var;
#endif

    /* a typeless pointer to the PostScript Aux service */
    void *psaux;


    /* ***********************************************************************
     *
     * Optional TrueType/OpenType tables
     *
     */

    /* grid-fitting and scaling table */
    TT_GaspRec gasp; /* the `gasp' table */

    /* PCL 5 table */
    TT_PCLT pclt;

    /* embedded bitmaps support */
    FT_ULong num_sbit_scales;
    TT_SBit_Scale sbit_scales;

    /* postscript names table */
    TT_Post_NamesRec postscript_names;

    /* glyph colors */
    FT_Palette_Data palette_data; /* since 2.10 */
    FT_UShort palette_index;
    FT_Color *palette;
    FT_Bool have_foreground_color;
    FT_Color foreground_color;


    /* ***********************************************************************
     *
     * TrueType-specific fields (ignored by the CFF driver)
     *
     */

    /* the font program, if any */
    FT_ULong font_program_size;
    FT_Byte *font_program;

    /* the cvt program, if any */
    FT_ULong cvt_program_size;
    FT_Byte *cvt_program;

    /* the original, unscaled, control value table */
    FT_ULong cvt_size;
    FT_Int32 *cvt;

    /* A pointer to the bytecode interpreter to use.  This is also */
    /* used to hook the debugger for the `ttdebug' utility.        */
    TT_Interpreter interpreter;


    /* ***********************************************************************
     *
     * Other tables or fields. This is used by derivative formats like
     * OpenType.
     *
     */

    FT_Generic extra;

    const char *postscript_name;

    FT_ULong glyf_len;
    FT_ULong glyf_offset; /* since 2.7.1 */

    FT_Bool is_cff2; /* since 2.7.1 */

#ifdef TT_CONFIG_OPTION_GX_VAR_SUPPORT
    FT_Bool doblend;
    GX_Blend blend;

    FT_UInt32 variation_support; /* since 2.7.1 */

    const char *var_postscript_prefix; /* since 2.7.2 */
    FT_UInt var_postscript_prefix_len; /* since 2.7.2 */

#endif

    /* since version 2.2 */

    FT_ULong horz_metrics_size;
    FT_ULong vert_metrics_size;

    FT_ULong num_locations; /* up to 0xFFFF + 1 */
    FT_Byte *glyph_locations;

    FT_Byte *hdmx_table;
    FT_ULong hdmx_table_size;
    FT_UInt hdmx_record_count;
    FT_ULong hdmx_record_size;
    FT_Byte *hdmx_record_sizes;

    FT_Byte *sbit_table;
    FT_ULong sbit_table_size;
    TT_SbitTableType sbit_table_type;
    FT_UInt sbit_num_strikes;
    FT_UInt *sbit_strike_map;

    FT_Byte *kern_table;
    FT_ULong kern_table_size;
    FT_UInt num_kern_tables;
    FT_UInt32 kern_avail_bits;
    FT_UInt32 kern_order_bits;

#ifdef TT_CONFIG_OPTION_BDF
    TT_BDFRec bdf;
#endif /* TT_CONFIG_OPTION_BDF */

    /* since 2.3.0 */
    FT_ULong horz_metrics_offset;
    FT_ULong vert_metrics_offset;

#ifdef TT_SUPPORT_SUBPIXEL_HINTING_INFINALITY
    /* since 2.4.12 */
    FT_ULong sph_found_func_flags; /* special functions found */
                                   /* for this face           */
    FT_Bool sph_compatibility_mode;
#endif /* TT_SUPPORT_SUBPIXEL_HINTING_INFINALITY */

#ifdef TT_CONFIG_OPTION_EMBEDDED_BITMAPS
    /* since 2.7 */
    FT_ULong ebdt_start; /* either `CBDT', `EBDT', or `bdat' */
    FT_ULong ebdt_size;
#endif

    /* since 2.10 */
    void *cpal;
    void *colr;
} TT_FaceRec;


/* *************************************************************************
 *
 * @struct:
 * TT_GlyphZoneRec
 *
 * @description:
 * A glyph zone is used to load, scale and hint glyph outline
 * coordinates.
 *
 * @fields:
 * memory ::
 * A handle to the memory manager.
 *
 * max_points ::
 * The maximum size in points of the zone.
 *
 * max_contours ::
 * Max size in links contours of the zone.
 *
 * n_points ::
 * The current number of points in the zone.
 *
 * n_contours ::
 * The current number of contours in the zone.
 *
 * org ::
 * The original glyph coordinates (font units/scaled).
 *
 * cur ::
 * The current glyph coordinates (scaled/hinted).
 *
 * tags ::
 * The point control tags.
 *
 * contours ::
 * The contours end points.
 *
 * first_point ::
 * Offset of the current subglyph's first point.
 */
typedef struct TT_GlyphZoneRec_ {
    FT_Memory memory;
    FT_UShort max_points;
    FT_Short max_contours;
    FT_UShort n_points;  /* number of points in zone    */
    FT_Short n_contours; /* number of contours          */

    FT_Vector *org;  /* original point coordinates  */
    FT_Vector *cur;  /* current point coordinates   */
    FT_Vector *orus; /* original (unscaled) point coordinates */

    FT_Byte *tags;       /* current touch flags         */
    FT_UShort *contours; /* contour end points          */

    FT_UShort first_point; /* offset of first (#0) point  */
} TT_GlyphZoneRec, *TT_GlyphZone;


/* handle to execution context */
typedef struct TT_ExecContextRec_ *TT_ExecContext;


/* *************************************************************************
 *
 * @type:
 * TT_Size
 *
 * @description:
 * A handle to a TrueType size object.
 */
typedef struct TT_SizeRec_ *TT_Size;


/* glyph loader structure */
typedef struct TT_LoaderRec_ {
    TT_Face face;
    TT_Size size;
    FT_GlyphSlot glyph;
    FT_GlyphLoader gloader;

    FT_ULong load_flags;
    FT_UInt glyph_index;

    FT_Stream stream;
    FT_UInt byte_len;

    FT_Short n_contours;
    FT_BBox bbox;
    FT_Int left_bearing;
    FT_Int advance;
    FT_Int linear;
    FT_Bool linear_def;
    FT_Vector pp1;
    FT_Vector pp2;

    /* the zone where we load our glyphs */
    TT_GlyphZoneRec base;
    TT_GlyphZoneRec zone;

    TT_ExecContext exec;
    FT_Byte *instructions;
    FT_ULong ins_pos;

    /* for possible extensibility in other formats */
    void *other;

    /* since version 2.1.8 */
    FT_Int top_bearing;
    FT_Int vadvance;
    FT_Vector pp3;
    FT_Vector pp4;

    /* since version 2.2.1 */
    FT_Byte *cursor;
    FT_Byte *limit;

    /* since version 2.6.2 */
    FT_ListRec composites;
} TT_LoaderRec;


FT_END_HEADER

#endif /* TTTYPES_H_ */


/* END */
